A shed-forming machine is, for pick finding, rotated slowly in a conventional manner by an auxiliary motor through a shiftable reduction gearing. The basic element of each pick-finding mechanism which is arranged between a weaving and a shed-forming machine is a single-tooth claw coupling, which assures that the weaving and shed-forming machines for the further weaving process cannot again be switched together phase-shifted. This single-tooth coupling is constructed relatively strong, namely, a great overlapping of the teeth exists to reduce the flank pressure. Furthermore, only a short time interval exists for effecting re-coupling, namely, the moment when the rotating teeth are aligned. Therefore, a strong spring is built into the pick-finding mechanism, which spring effects a timely and quick recoupling operation.
The strong spring is tensioned by operation of the pick-finding mechanism, which occurs preferably simultaneously with the uncoupling operation, which in turn is carried out by operation of either a switch lever of the pick-finding mechanism or an electromagnet. This tensioning of the spring requires considerable forces which, when tensioning with a switch lever, is a strong load on the operator and, during tensioning with an electromagnet, demands a voluminous electromagnet. Also, it is disadvantageous that the electromagnet works very suddenly, which results in additional loads on the gearing. However, the latter operation does have the advantage that the operation of the electromagnet by means of a push button can be released from any point of the weaver stand.
It is also possible to use the pick-finding mechanism with its motor for the slow-speed, called the creeping speed, operation of a weaving and shed-forming machine. Here too, at the end of the operating process, re-engagement of the coupling is effected by means of an initially tensioned spring.
A goal of the invention is therefore to provide a mechanism which assures a simple mechanical or electromagnetic but not too sudden disengagement of the coupling, with a simultaneous tensioning of the return spring for effecting the re-engagement of the coupling, and without requiring substantial physical effort of the operating personnel.